The fact that the nForce4, nForce4 Ultra, and nForce4 SLI are identical core chips is important to anyone comparing board performance. SLI can be an expensive option, and if you don't require it, the nForce4 Ultra provides a single video solution with a chipset that performs exactly the same as the SLI chipset in single video. If you can give up a few more features, then the base nForce4 is an even cheaper solution that can give the same level of single video performance. This means that you can look at the performance of one member of the nForce4 family - an nForce4 SLI motherboard tested with single video, for example - and be fairly confident that the lower members of that family have a chipset that performs exactly the same. The different motherboard designs and chips selected for features might have some small impact on final performance for different nForce4 boards from the same manufacturer, but the differences will mainly be the available features on the various boards.